Fire-box for steam-boiler furnaces.



PATENTED MAY J. LIVINGSTONE. FIRE BOX FOR STEAM BOILER FURNACES.

APPLIOATION FILED JULY 21, 1906.

2 SHEETS-SHEET 1 n w m \N N M m6 m N L N H Q w BYM t" v ATTORNEYSPATBNTED MAfi, 1907.

J. LIVINGSTONE. FIRE BOX FOR STEAM BOIL ZR FURNAGES. APPLICATION FILEDJULY 33 SEEETS-SREET 2-.

q ATTOHA/E r9 rmrr'nn shares ge r r nn'r ora on.

JOHN LIVINGSTONE, MONTREAL, QUEBEC-,CANADA,

' FIRE-BOX FOR STEAM-BQELER FURNAQES.

To all whom it may concern.-

Be it known that 1, JOHN Lrvmos'ronn, a subject of the King of England,residing at Montreal, Quebec, Canada, have invented a new and usefulImprovement in Fire-Boxes for Steam-Boiler Furnaces, of which thefollowing is a specificationf v My invention is in the nature of certainimprovements in the fireeboxes of steam boiler furnaces and especiallythe furnaces of locomotive boilers.

' It is designed to accomplish several im-- portant results, prominentamong which are. First, to contribute to the strength and stability ofthe boiler around the fire-box by maintaining, while-in service, thenatural elasticity of the material, avoiding the burn ing of the innerends of the stay-bolts and avoiding those strains which ordinarily existbetween the stay-bolts and the outer and inner walls of the fire box dueto high tempera, tures of unequal distribution. Secondly, to

secure a more perfect combustion of, usually,

unconsumed carbon, and thus economize fuel and avoid the nuisance ofsmoke. Thirdly, to assure a continuous production of free l1ydrogen inthe fire-box and fourthly, to give relief from explosion.

The instrumentalities invented by me for securing the results under-thefirst heading are precisely the same as those which accomplish theresults under the second, third and fourth headings and theseinstrumentalities consist in a very simple and practical appli 5 cationof hollow stay-bolts which, While notnew in themselves, involve, whenconstructed and applied in accordance with my invention, the mostimportant results in 4 steam boilerfurnaces.

Figure 1 is a vertical longitudinal section through the fire-box of alocomotive boiler.

' Fig. 2 is a vertical transverse section through the same, on line 22of Fig. 1. .Fig. 3 is an enlarged central section of one of the crownstay-bolts and Fig. 4 is a similar view of one of the horizontalstay-bolts as used at the sides, back and front of the fire-box.

In the drawing, A represents the outer wall and B the inner wall of thatportion of a locomotive boiler which surrounds the firebox 0.

D are stay-bolts WlllCll connect the crown sheet of the furnace to thetop portion of the outer wall and E are stay-bolts which 0011- necttheouter and inner walls atthe sides,

bolts E. 'As't back and front ends of the fire-boar.

' Specification of Letters Patent. Application filed July 21,1906.Serial No. 327.157-

Patented- May '7, 1907.

The stay-bolts as shown are all screw threaded their entire length, butthey may be I threaded only at the ends where they pass, through theouter and inner walls of the I prefer the Vhitworth standard to thel-threads.

boiler.

7 Their outer ends are firmly rivetedor upset to form heads or they maybe made fixtures in any other suitable way.

The horizontal stay-bolts E, vsee- Fig. 4;, have acentral longitudinalhole a through them from end to end and embody, no constructive novelty.The stay-bolts D, of't lie, crown sheet are, however, speciallyconstructed, as seen in Fig. 3.- They have a centralglongitudinal hole(1, which does not go all the way through, but stops short of the outerend of the stay-bolt, so thatit does not communicate with theouter air.It does go all the way. through the inner end of the bolt, however, andit cornmu nicates wit a number of small holes dzl. drilled transverselyinto the stay-bolt'and opening on the outer side into the steamspace inthe boiler be tween its two walls, sc -that steam from the steam spacemay gain access to the central, hble in the stay-bolt and flow ina'small stream into the fire boX. The steam ex.-

pands in the central hole; it there meets and fusion of the heat isqhickened to the outer wall; the side sheets, back head and front endreceiving the radiant'heat-of the fire at the same time as the crownsheet, and all at the same time with the radiant heat up (Z and byconduction up D and by diffusion througlf the water, and with the heatat the outer wall confined by the lagging, an equilibration of thetemperature between the two walls is attained. The service of the steamin the central hole (1 is also of value to the materiahin that, whereasin solid stay b'olts theimate'rialbeicomes fatigued and weakened. inservice, it saves and sustains the material in its elastic strength,provided the iron is freefrom the brittleness. The central hole d isalso a safety hole in case of breakagefor though the natural supply ofsteam from openings (1 is invisible, the breakage of a bolt would causea visible 'escape of steam to give notice of suchbreakagc of'a bolt orbolts, and the same remarks apply" to the opening e in stay s stream ofsteam. passes through the highly heated end of these staybolts, theissuing steam is invisible, and superheated to the point of disruptioninto its constituent gases, oxygen and hydrogen. Just at this point twoimportant and simultaneous results may be noted. The first is thecooling of the end of the stay-bolt in the inner wall by the escapingsteam and inc'reas' ing the strength, stability, and longevity of thestay-bolt, by taking away its damaging excess of heat, and the second isin utilizing this heat by giving it to the steam, for superheating thesame and rendering it susceptible to disruption with the consequentforma-' tion of water gas by, the association of its gases with theincandescent particles of the fuel.

. The streams of superheated steam form,

when disrupted,'fuel gases which mingle with the oxygen of the airpassing through the,

lower stay-bolts, and produce an intense combustion which burns up thesmoke. and carbon particles.

In the ordinary way of there are three forms of loss from out of thecombustibles, irrespective of losses by burn ing coal weighted withconstituent incombustibles. The three forms of loss, are; first, the

loss of-the volatile constituents of bituminous coal. Second, the lossby the formation of the always forming carbonic .oxid. Third, the lossby the escape, unconsumechol the carbon particles from the furnace, inpart lod ingin the front end, where they accumu ate and impair thedraft, and in part as sparks through the smoke stack, sometimes causingfires.

Professor Goss, the scientist of- Purdue University, has determined, bytest, that the weightof sparks and cinders, which escape as above,unconsumed, to the front end and outer air, may in connection withnarrow fire boxes equal 20 per cent. of the fuel fired. Tlie three formsof loss even with careful firing in the fire boxes generally" inservice, may

aggregate 50 per cent. of the weight of the The affinity of hydrogen (1,for oxygen,-

and. the oxygen always present when wanted in never cooling volumes bywav of the tubular channels e n'iail'itains the temperature above thetemperature at which carbon ig burning the fuel, I

nites, and (2) the affinity of hydrogen for carbon, makes it the gas toovertake and burn 1n the fire-box the carbon particles which wouldotherwise escape to the front end as cinders and to the smoke stack as.

sparks. 'When the volatile portion of ti 9 bituminous coal is spreadover the red fuel, it rises above the fire bed and. quick as a flash itis in the air as smoke; and when the solid coal under the influence ofthe incandescent lire bed gives o'll unburned, partly burned, or cokedportions called carbon particles, they rise in the furnace and passthrou h the tubes .tothe front end or out of the stac ,and there is noother gas but hydrogen to'overtake'and consume the carbon particleswhile they are in the fire-box, because there is no othergas equal'toit'in-diifusive and refractive power; 7

it d ifl uses relatively at the rate of four to one foroxygen, thevelocity of its atoms is 6,050

ond, all combining with the first stage of burning on-the grate andperfected by the production of hydrogen at (Z and by the union of thecarbonic oxid with. the oxygen from Most efforts to superhcat anddisrupt steam in a fire-box involve a destruction of the ma tcrialforming the instrumentalities, but in. my invention, it will be seen,that the gassifying of the steam is made to' cure an existing evil,namely, the burning of the inner ends of the stay-bolts, so that lsecure two advantageous results without the hitherto attomh antobjections of either, or in other words while securing a greatdesideratum in stimu-.

lating combusthm, l by the same instrumentalities and at the sametimeywithout other expense, dispose of very serious evil, by thepreventing of the burning of the inner ends of the stay-bolts and theavoidance-of differential temperature strainsat the anchorage points ofthe stay bolts in the, walls of the boiler. J It. is Well known that therailway coinpanies are greatly embarrassed 'by the breaka e ofstay-bolts. abnormal breakage is in the greater temperature andexpansion of the inner sheet (next the lire) acting on the bolts laut 1nthe outer sheet of the -[ire-box \vhcrc thc tcxmmraturc is less. Thatcause produces differential expansion and contraction in the stay--bolts in. the varying tci'nperaturos of the lire-box, which sooner orlater, causes crystallization and breakage. The, danger increases withevery bolt broken, sometimescausing cx I plosions and loss of life withappalling uddennoss. When from any cause, the ('onduc tion through thematerial is impaired, and any part ofthe iron \vn'lun the bo1ler l)ecomes red hot, then wager or steam released The allegedcause of tho by abreaking stay -bolt will, in tom-hing the red hot iron, cause a sudth ncxg'losion.

l have det'ern'uned by tests that the gases 85 feet a second with oxygen1,514, and nitrogen, (which aids the draft) 1,616 feet asec released bydisruption may be continuously 1 o frbm explosions in the small holes dd and in the center hole (1, the expansion losing its en ergy'by itsdissipation through the fire-box, tubes, and smoke stack in the outerair.

Other dangers arise from burning: When stay-boltends burn, the burningmay follow 2o i1npurities from the water.

' heat, the iron loses its cohesion and hardness,

the line of the fibers up the bolt until cooled by the water, and thecooling may not occur until half the bolt is destroyed, especially if itis coated all round with non-conducting In such burning becomes lessenedin tenacity, and sometimes its molecular form may be altered to acrystalline structure, and the sheets in expand- 2 5 ing are antagonizedthe expanding bolts and crack. I

By reason of direct exposure to high heat the ends of stay-bolts exposedto the fire, are

quickly destroyed since theyhave no protection by touch with the air,envelopment riveting thereon.

in steam, or by conduction of their heat at the junction of the bolt andthe sheet; their connection there being only a mechanical connection byscrewing into the sheet and The tenacity of the iron therefore becomesless, sometimes st much so that it fails to endure the steam pressure,which forces the sheet out from the threads 7 and pulls the head throughthe sheet.

The railway companies are also continuous losers and the people injuredby reason of the excessive waste of fuel, in smoke escaping through thesmoke stack, and partly burned coal, escaping as sparks, causing damagesI 49am suits for damages, also by reason of the loss and waste ofcinders, lost 'to the fire, by

esca ing through the tubes to the front end of t 1e locomotive and thusinterfering with the draft. There is also much interference in makingsteam, by reason of coatings of soot in the tubes, the soot being anon-conductor, preventing the conduction of the heat through the tubes.

Coatings of soot in the tubes come-from ditions whichburn the carbon tocarbon di- 'ox'id, and a good natural draft to lead the carbon dioxidthrough the tubes to the stack,

in its passage it will dissolve the sootin the and outer sheets of thefire-box.

imperfect combustion, but given the con-.

ages, and while adding more to that cost, the

drilling of tell tale holes in the ends, is of dis- My invention inmeeting the various objections noted serves 1. To effect an equilibriumin the, temperature between the inner 2.. To increase the steam servicefro'm the heating surface without enlargement of the boiler. 3. Toquicken the service of heat tothe outer sheet at even time with itsservice to the "inner sheet by radiation and the uniform diffusion ofthe heat in the water by conduction; 4. To cause the combustibles nowwasted as smoke, the cinde'rs now lost in the front end,-' (thereimpairing the draft) and the sparks now sent out of the smoke. stack, tobe burned,in the fire-'box'. ends of stay-bolts from burning and lessenthe expansion of the bolts with relief from cracking, in the expandingsheets. 6. To convert continuously, when in service, the solid fuel intocombustible gases. 7. To furnish oxygen to burn the combustible gasesformed in the process of burning. 8. To dissolve the soot, as it settlesin the tubes; 9. i To promote a draft to aid in the passage of thealways forming carbonic acid through the tubes to the smoke stack. 10.To produce and burn hydrogen in the fire-box, -to maintain thetemperature and therewith oxygen consume the gases, cinders, sparks,andsmoke, by taking them into union. 11. To give general relief inconditions which cause explosions.

I claim 1. A steam boiler furnacehaving the outer f."

and inner Walls of the fire box connected by hollow stay bolts havingsolid outer ends and opening into the furnace at their inner ends" andhaving one or more lateralopenings" establishing communication betweenthe inte rior of the boiler and the hollow stay bolt.

2. Asteam boiler furnace having crown sheet stay bolts formed with solid0 iter e'nds and steam spaces opening into the fire box.

3. A steam boiler furnace having crown sheet stay bolts formed withsolid outer ends and steam spaces opening into the fire 'box andhorizontal staylbolts connecting the two walls of the lower part of thefire box and having an channels extending entirely throu h thesame.

"4. hollow stay bolt for a "steam boiler having one end made solid andclosed, the other end open and one or inorelateral inlets to theinterior between. the ends. 1

' J OHN' LIVINGSTONE. Witnesses:

E. J. FAY, E. H. WEBB.

5. To protect the

